Fisher President Series XP-18 - surround resealing

[mikehd]

Hi all,

I don't have a lot of experience with vintage hi-fi gear. Recently a friend and I have been cleaning up and trying to get running a Sansui G-9700, a Carver Receiver 2000, and this pair of Fisher President XP-18 speakers. The speakers are working well, the G-9700 works mostly (tuner needs attention, and it just started to drop the right channel), and the Carver likely needs the power supply rectifier diodes replaced (among other things?).

I have been quite impressed by their overall sound quality. Being as old as they are, I thought it might be time to reseal the surrounds. I purchased a product from "vintage-ar" on eBay based after reading on other forums that this product is used on AR cloth surrounds. It appears to be a butyl rubber in toluene solution.

While I was initially only planning on doing the woofers, I noticed that the upper mid range drivers have very pliable, almost limp, surrounds, almost as if they're not sealed. The lower mid range drivers' surrounds are noticeably stiffer.

Should I proceed with sealing the woofers only, or should the mids get some attention as well? I do notice that the mids seems to break up a bit with high intensity music. I was thinking that maybe more surround stiffness would help it cope.

I'm driving these with an Adcom GFA-545-ii/GFP-565 amp/pre-amp. I put my ADS L710s on this same stack with no similar break up that I could hear on the same track. It may be that it just how the Presidents are, and I should just leave them as is and enjoy.

Here's a few images of the Presidents.






Thanks for your advice.

 

[swechsler]

Should I proceed with sealing the woofers only, or should the mids get some attention as well? I do notice that the mids seems to break up a bit with high intensity music. I was thinking that maybe more surround stiffness would help it cope.

The mids should have sealed backs. If you gently press in on the cone (for the upper mid, you can probably press on the dust cap, for the lower, use a finger on either side), do you feel resistance, or does it go freely straight back? If the latter, the surrounds need sealing. If the former, they're probably fine.

If you're hearing distortion, there's probably something loose or torn.

And welcome to AK.

ETA: you didn't mention it, but the crossover caps are due for an update. Do these speakers have any level controls? Dirty controls can cause distortion as well.

 

[mikehd]

The mids should have sealed backs. If you gently press in on the cone (for the upper mid, you can probably press on the dust cap, for the lower, use a finger on either side), do you feel resistance, or does it go freely straight back? If the latter, the surrounds need sealing. If the former, they're probably fine.

If you're hearing distortion, there's probably something loose or torn.

And welcome to AK.

ETA: you didn't mention it, but the crossover caps are due for an update. Do these speakers have any level controls? Dirty controls can cause distortion as well.

Mids go freely back. I'll re-inspect the surrounds but didn't see anything loose or torn in my initial inspection. I'll add the cap update to my list. The mids and treble have level controls. I'll add cleaning these as well to the list.

Thanks for your help and welcoming me to the forum.

 

[mikehd]

First coat is on all 3 drivers in each cabinet. Surprisingly easy to apply.

 

[doctorolds]

What did you seal them with?

 

[mikehd]

I found a series of forum posts on classicspeakers.net in the AR sub I believe, and eventually found a lead for an individual on eBay that is selling the "dope". From what I read, it is a butyl rubber in toluene solution. The eBay seller is "vintage_ar".

 

[doctorolds]

Okay, that's a good source. Did you achieve the desired results?

 

[mikehd]

So far they're looking good. I don't think I need a second coat, but thought I'd wait 24 hours for the solvent to evaporate before testing.

 

[f0427ea]

Hi all,

A pair of Fisher President XP-18 speakers, the speakers are working well, and I have been quite impressed by their overall sound quality.

Here's a few images of the Presidents.

View attachment 2816203

View attachment 2816223


Thanks for your advice.

Fisher got it right with their XP consolette series of speakers , once you get the tired ,old Bill Hecht 'Fried Egg' Dome Tweeter's (and capacitors) replaced
they are most certainly keepers, my sets aren't going anywhere soon.

got a set of XP 15's



and a set of XP 15b's



both sets are very nice sounding indeed

 

[mikehd]

Fisher got it right with their XP consolette series of speakers , once you get the tired ,old Bill Hecht 'Fried Egg' Dome Tweeter's (and capacitors) replaced
they are most certainly keepers, my sets aren't going anywhere soon.

got a set of XP 15's

and a set of XP 15b's

both sets are very nice sounding indeed

Nice! What replacement tweeters did you use? Are the mids and woofers original drivers?

 

[mikehd]

I treated the level controls with DeOxit, photographed the crossovers, placed a few orders for new crossovers, and gave the freshly sealed surrounds a test listen. I'll admit that I didn't hear much, if any, difference in the sound. I'll need to listen to more types of music.

In case anyone was curious about the crossovers:

 

[swechsler]

Odd that Fisher put all the inductors so close together, and in the same orientation. Typically you want to space them farther apart, or mount them on different axes to reduce interference between them.

 

[robnec]

Hello. I have xp18 speakers and they are exellent. Nothing beats the quality and speed of bass coming from 18 inches drivers. I had to replace tweeters and small mid drivers in mine.
I wanted to ask you for a favor. Could you check part number of small mid drivers when you get a chance? I see sometimes a replacement on auction site but I misplaced my notes and I do not know which ones are correct. Thank you in advance. Robert.

 

[mikehd]

Hello. I have xp18 speakers and they are exellent. Nothing beats the quality and speed of bass coming from 18 inches drivers. I had to replace tweeters and small mid drivers in mine.
I wanted to ask you for a favor. Could you check part number of small mid drivers when you get a chance? I see sometimes a replacement on auction site but I misplaced my notes and I do not know which ones are correct. Thank you in advance. Robert.

No problem. I'll be back inside the cabinets as soon as my caps arrive. What tweeters did you use to replace the fried eggs?

 

[robnec]

Hello. I used Madison soft domes and small drvers which I had on hand. It helps that one can adjust high and medium tones in the back. I have replaced all caps /expensive move/, resistors and ran Kimber Kable wires inside. I also put DynaMat on the inside walls. They are huge and as you can see there is no bracing. The new cloth for the grill too. Robert.

 

[Nat]

I think that inductor spacing and orientation matters more with lower efficiency speakers that require higher power, which would create stronger fields to interact. Back when those were made, 50 wpc channel was big power.
Those black caps are known for degrading over time, so it's worth recapping while you are in there. If you want the original sonic signature, replacing them with new electrolytics will probably be your best bet since the ESRs will probably be closer than with film caps. And it'll be cheaper. But many people will tell you that film caps are the way to go for more sonic bliss, and a large percentage of those people will also insist that one company or another is the best bet. Price usually seems to be a correlative factor - more money must mean better sound, right? But many people are satisfied with Daytons, which are relatively inexpensive.

 

[mikehd]

I think that inductor spacing and orientation matters more with lower efficiency speakers that require higher power, which would create stronger fields to interact. Back when those were made, 50 wpc channel was big power.
Those black caps are known for degrading over time, so it's worth recapping while you are in there. If you want the original sonic signature, replacing them with new electrolytics will probably be your best bet since the ESRs will probably be closer than with film caps. And it'll be cheaper. But many people will tell you that film caps are the way to go for more sonic bliss, and a large percentage of those people will also insist that one company or another is the best bet. Price usually seems to be a correlative factor - more money must mean better sound, right? But many people are satisfied with Daytons, which are relatively inexpensive.

Thanks for the info. I ended up with electrolytics as I thought it would be best to try to match the old styles. I spent about $30 for a complete set as shown in the images above. The 6uF turned out to be the most difficult to find. Ended up buying those on eBay. The others were available from Parts Express. Not much choice of ESR. I tried Mouser, Newark, and Digi-key but they didn't have much available for my speakers. In fact, they had zero 6uF electrolytic caps, but many 5.8 or 6.2. Wasn't sure how these would effect the crossover performance so played it safe with 6uF nominal caps.

 

[doctorolds]

Just an FYI @mikehd, you can run two or more capacitors in parallel to achieve the desired value. As an example, a 3.8uf and a 3.2uf would add up to 7uf. I hope that you are happy with the sound of your speakers when you complete them!

 

[mikehd]

Just an FYI @mikehd, you can run two or more capacitors in parallel to achieve the desired value. As an example, a 3.8uf and a 3.2uf would add up to 7uf. I hope that you are happy with the sound of your speakers when you complete them!

Thanks! That will likely come in handy. Is the ESR value of the capacitor much of an issue for crossovers?

 

[doctorolds]

Yes and no, it depends upon who you talk to, some people say it's negligible, some say add some resistance, some say go with replacements of the same type. Crossovers and capacitor replacements are something you could read about forever it seems? Personally, I usually use the same type as OEM, it's my choice, not gospel.